Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Dec 20;23(1):1032.
doi: 10.1186/s13063-022-06974-7.

The Knee-Fix study: study protocol for a randomised controlled trial evaluating cemented and cementless components in total knee arthroplasty

Mei Lin Tay  1   2 , Nina Zeng  3 , Sherina Holland  3 , Ali Bayan  3 , Bill J Farrington  3 , Rupert van Rooyen  3 , Rob Sharp  3 , Robert S J Elliott  3 , Matthew L Walker  3 , Simon W Young  3   4
Affiliations

The Knee-Fix study: study protocol for a randomised controlled trial evaluating cemented and cementless components in total knee arthroplasty

Mei Lin Tay et al. Trials. .

Abstract

Background: Total knee arthroplasty (TKA) is an effective procedure for patients with a variety of knee conditions. The main cause of aseptic TKA failure is implant loosening, which has been linked to poor cement mantle quality. Cementless components were introduced to offer better longer-term biological fixation through osseointegration; however, early designs led to increased rate of revision due to a lack of initial press-fit and bony ingrowth. Newer highly porous metal designs may alleviate this issue but randomised data of fully uncemented TKA (tibial, femoral, patella) is lacking. The aim of the Knee-Fix study is to investigate the long-term implant survival and patient outcomes of fully uncemented compared with cemented fixation in TKA. Our study hypothesis was that uncemented TKA would be as clinically reliable and durable as the gold-standard cemented TKA.

Methods: The Knee-Fix study is a two-arm, single-blinded, non-inferiority randomised controlled trial with 160 patients in each arm and follow-up at 6 weeks, 6 months, 12 months, 24 months, 5 years and 10 years. The primary outcome of interest is implant fixation, which will be measured by assessment of postoperative progressive radiolucencies with the Knee Society Total Knee Arthroplasty Roentgenographic Evaluation and Scoring System. Secondary outcome measures are patient-reported outcomes, measured using Oxford Knee Score (OKS), International Knee Society System (IKSS), Forgotten Joint Score-12 (FJS-12), EuroQol (EQ-5D-5L), VAS Pain, Patient Satisfaction Score and Net Promoter Score.

Discussion: While cemented fixation remains the gold standard, a growing proportion of TKA are now implanted cementless. Highly porous metal cementless components for TKA can offer several benefits including potentially improved biological fixation; however, long-term outcomes need further investigation. This prospective study will help discern long-term differences between the two techniques.

Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12616001624471 . Registered trial name: Knee-Fix study (Cemented vs Uncemented Total Knee Replacement). Registered on 24 November 2016.

Keywords: Aseptic loosening; Cement fixation; Cementless; Radiolucencies; Total knee arthroplasty.

PubMed Disclaimer

Conflict of interest statement

SWY, MLW and RJSE are paid consultants and receive research support from Stryker Orthopaedics. SWY receives research support from Smith & Nephew. The other authors declare that they have no competing interests.

References

    1. Ritter MA, Meneghini RM. Twenty-year survivorship of cementless anatomic graduated component total knee arthroplasty. J Arthroplasty. 2010;25:507–513. doi: 10.1016/j.arth.2009.04.018. - DOI - PubMed
    1. Kim YH, Park JW, Jang YS. 20-year minimum outcomes and survival rate of high-flexion versus standard total knee arthroplasty. J Arthroplasty. 2021;36:560–565. doi: 10.1016/j.arth.2020.07.084. - DOI - PubMed
    1. Chalmers BP, Syku M, Joseph AD, Mayman DJ, Haas SB, Blevins JL. High rate of re-revision in patients less than 55 years of age undergoing aseptic revision total knee arthroplasty. J Arthroplasty. 2021;36:2348–2352. doi: 10.1016/j.arth.2020.12.008. - DOI - PubMed
    1. Kurtz SM, Lau E, Ong K, Zhao K, Kelly M, Bozic KJ. Future young patient demand for primary and revision joint replacement: national projections from 2010 to 2030. Clin Orthop Relat Res. 2009;467:2606–2612. doi: 10.1007/s11999-009-0834-6. - DOI - PMC - PubMed
    1. Koh CK, Zeng I, Ravi S, Zhu M, Vince KG, Young SW. Periprosthetic joint infection is the main cause of failure for modern knee arthroplasty: an analysis of 11,134 knees. Clin Orthop Relat Res. 2017;475:2194–2201. doi: 10.1007/s11999-017-5396-4. - DOI - PMC - PubMed

Publication types